We're big oatmeal fans. 
Alton Brown had an oatmeal episode of Goods Eats some time back. I believe that he explained that "steel cut" are chopped, uncooked oats, "old-fashioned, long cooking" oats are rolled (squished) oats that have been steam-cooked to an extent and "instant" are rolled oats that have been steam-cooked completely.
Alton's "Overnight Oatmeal" recipe is our absolute favorite:
http://www.foodnetwork.com/recipes/a...ipe/index.html
We use whatever dried fruits we feel like using but I think our favorite combo is half raisins, half dried cranberries. We use fat-free half & half and sometimes add a few tablespoons of flax seed that I grind in our never-used-for-coffee grinder.
I make this recipe several times every week. The leftovers keep very well for a couple of days. A little zap in the microwave to warm it up is all it takes.
I have found, however, that our old (30-year-old) wedding gift crock pot works the best. Our newer crock pots, I swear, are hotter than the old one and tend to scorch any low-liquid food I make in it. The old one makes a perfect batch which is ready to eat in the morning. Since finding this recipe I've used our old crockpot more than in all the years that we've had the thing!
Jane
Every human being must be viewed according to what it is good for; for none
of us, no not one, is perfect; and were we to love none who had
imperfections, this world would be a desert for our love.
--- Thomas Jefferson